A class of fractional-order hyperchaotic system and its application in spread spectrum communication

Abstract

A class of fractional-order hyperchaotic system is introduced and its basic dynamical properties are investigated by means of theoretical analysis and numerical simulation. Systemic sensitivity to the orders of all involved derivatives is analyzed by stud-ying the Lyapunov exponent spectrum and bifurcation diagram. The class of fractional-order system presents hyperchaos, chaos, and periodic behaviors when the fractional orders vary continuously. Based on synchronization of the fractional-order hyperchaotic system and the theory of spread spectrum communication, we propose a new scheme for general spread spectrum communication. In contrast to PN code in the traditional CDMA communication, the scheme uses the chaotic signal sequence as a spread spectrum address code of direct sequence spread spectrum communication. Then, a circuit of spread spectrum communication based on the fractional-order hy-perchaotic system is designed. The validity and feasibility of this scheme are certificated in Multsim platform.

Keywords

• hyperchaotic systems
• synchronization
• spread spectrum communication
• spread spectrum code sequence